textproduct: Albany

WHAT HAS CHANGED

No significant changes were made with this update as the forecast remains on track.

KEY MESSAGES

1) Isolated to highly scattered showers and non-severe thunderstorms are expected this afternoon with no significant resulting impacts.

2) Temperatures are trending above normal for next week with increasing humidity. However, due to the potential for showers and thunderstorms, it is uncertain at this time how hot it will become.

DISCUSSION

KEY MESSAGE 1...

A cold front is approaching from the northwest this afternoon, attached to a weak surface low tracking overhead. Aloft, a mid- level shortwave is shifting to our east, its axis centered almost along the border of New York and western New England. Some showers have popped up mainly in the Southern Adirondacks and the Mid-Hudson Valley so far this afternoon, but coverage has been very isolated. Based on latest radar trends, most showers that have developed have either quickly dissipated or weakened before even attaining lightning. This is likely due to the several mid-level capping inversions seen on the 18z ALY sounding.

That said, given the clearing of clouds this afternoon, there is about 500 J/kg of mixed layer CAPE throughout our region with 40-50 kt of bulk shear, DCAPE around 600-700 J/kg, and PWATs in excess of 1". Therefore, given the forcing, though limited, from the cold front; surface low; and upper shortwave, there is potential for pop-up showers and perhaps a few thunderstorms to continue throughout the afternoon. While there are no significant impacts expected as a result of these showers and thunderstorms, especially given their isolated to highly scattered nature, there is potential for some resulting gusty winds. In fact, one shower in particular moved over the NYS Mesonet site within the last hour and produced a 41 mph gust. However, no severe thunderstorms are anticipated.

Showers could linger into a portion of the overnight, though any resulting precipitation will be very light in nature. Another low pressure system will track to the south of our area beginning overnight into tomorrow, but it looks to remain sufficiently south to only allow light rain showers to spread into a small portion of the Eastern Catskills, Mid-Hudson Valley, and southern Litchfield.

KEY MESSAGE 2... Confidence continues to increase for an upper level ridge to build across the eastern CONUS for much of next week with the crest of the ridge to the west over the Ohio Valley and upper Great Lakes. Nonetheless, a warmup is expected across the region as 850 hPa temperatures increase to +17 to +20C (about +2 to +2.5 STDEV). This will likely lead to nearly daily high temperatures well into the 80s with at least the lower 90s some days in the valleys from Monday through Friday. In addition, Gulf moisture advecting into the region will increase humidity levels with dewpoints rising into the 60s and possibly lower 70s. The combination of the higher humidity and warm to hot temps could lead to heat index values (feels- like temperatures) reaching at least heat advisory criteria on some days. The experimental NWS HeatRisk places most of eastern New York and western New England in the moderate to major risk for heat- related impacts beginning on Wednesday. With the high humidity, there will be little relief each night.

Being on the northeastern periphery of the ridge, multiple shortwaves may pass over the ridge ('ridge rollers') which could bring opportunities for showers and thunderstorms at times. Trends will be monitored for possible stronger storms, especially if they pass through during times of peak heating. While the passage of storms will help ease the heat for a short time, the high humidity will remain regardless. Timing and track of each shortwave remains uncertain and we will continue to monitor trends over the next several days. These shortwaves may also require adjusting of temperatures for those days as well.

AVIATION /00Z SATURDAY THROUGH WEDNESDAY/

VFR conditions expected through this evening, then patchy ground fog may develop toward and after midnight, mainly at KGFL with smaller chances (20-40%) at KPSF and KALB. Brief periods of IFR/LIFR conditions will be possible where fog forms. Any fog/low clouds should lift between 11Z-13Z/Sat, with VFR conditions then prevailing despite occasional high and mid level cloud patches, especially at KPOU.

West to northwest winds 5-10 KT will become light/variable shortly after sunset through Saturday morning, then trend into the north to northeast at 4-8 KT Saturday afternoon. Winds may shift into the south to southwest at similar speeds late Saturday afternoon at KPOU.

Outlook...

Saturday Night: No Operational Impact. NO SIG WX. Sunday: No Operational Impact. NO SIG WX. Sunday Night: No Operational Impact. NO SIG WX. Monday: No Operational Impact. NO SIG WX. Monday Night: No Operational Impact. NO SIG WX. Tuesday: Moderate Operational Impact. Chance of SHRA...TSRA. Tuesday Night: Moderate Operational Impact. Chance of SHRA...TSRA. Wednesday: Moderate Operational Impact. Chance of SHRA...TSRA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.